Well, there is another morsel, and it concerns the Jews.
The part that says "who say they are Jews, but are not, but are of the synagogue of Satan" ... isn't talking about people who claim to be Jews, it IS about Jews. Let me explain...
Jesus is having this message sent to Christians. Jews rejected the Messiah, and as such, were rejected BY the Messiah. They are heading for damnation. No if, ands or buts about it. Jesus Himself said to them that they will feel awful when their fathers and all nations enter in but they themselves are cast out into outter darkness.
You see, Isaiah said it. Isaiah told us who and what ISRAEL really is. He said that Israel are those who turn from sin (basically). What Isaiah was saying was reinforced and further explained by Paul. Paul wrote that the real Jew is not the one with blood ties to Jacob, but the one who is INWARDLY. Basically, and African who has a heart towards God and a desire to live for Him is more of a Jew than someone who is unsaved, rejects God, but can prove their geneology tie right back to king David. A lot of things the Paul taught weren't actually new teachings. They were things that existed already in the Hebrew text, such as circumcising the foreskin of your heart. That was what Moses originally taught, not Paul.
So, fast forward to Revelation and you see Jesus Himself essentially saying that "You see these Jews? These ones who have rejected Me? These, whom My bride will call "Judaizers" in times to come? They are not of Me. They do not belong to Me. Their persecution of you is of no command of Mine. In fact, I don't even know them and I have already cut them off."
Basically, that is what Jesus was saying to those Gentile/Jewish Christians in that Church. He was saying that their geneology means nothing to Him and they are not what they boast about - Gods special little people (for God Himself had cut them off, evidenced by all the suffereing and them being scattered).
I think, when people learn what "only a remnant will be saved" really means, they will know that Isaiah was talking about only a small number of Jacobs descendants will enter the Kingdom.
But when they also learn what "all of Israel will be saved", they will know that ISRAEL is all the saints, from every nation, tongue, creed, since even before Jacob was born. Job was no Hebrew, but he is indeed part of Israel, because he died in Gods will.
This is what Isaiah and Paul were saying ... and what Jesus was eluding to.
"They call themselves Jews, but are not, but are of the synagogue of Satan" - Jesus
Powerful, powerful words by our Lord. But too often people forget who the audience was - Christians - and they forget about the persecution of the Christians by the Judaizers. But God has told us, that not even the Jews are in any position or right to tell us that we are wrong in Jesus.
Think on it. Read it. Pray about it ... if you have a problem with it due to mainstream teaching and rumor spreading. This has nothing to so with "fake Jews", such as these Hebrew Israelites walking around, or these people who go through the hard process of converting to Judaism, and then are called "Jew" ... but have no bloodline to Jacob. Now, this isn't what Jesus is talking about at all. He is talking about JEWS, but because of their rejection of Him, He has rejected them.
And since Paul was called and sent by Jesus, is not Paul correct when he says that the REAL JEW is one who is inward (children of faith and obedience) and not one outwardly (bloodline of Jacob)?
Jesus warned the Jews not to boast of that, saying that God could turn the very stones into sons of Abraham. lol They trust in their bloodline and traditions to save them, but they are already doomed.
Only a remnant...
But ALL of Israel will be saved.
EDIT: and this is a Messianic Prophecy, that they would reject the Messiah (God) and in turn, will be rejected BY Him.